essex-monkey

hi , im looking to change the oil in my cosworth this week but ive not owned it too long so im unsure which oil is best to use, the engine has been rebuild about two - three years ago so i guess its best described as slightly worn lol, just want to do my own service for piece of mind really , just seems to be alot of different oils used by people . thank you

CosworthGuy

Its all down to personal choice mate. Some say 5w50 some others say 10w60. Its a minefield lol. Where in lincs are you?

essex-monkey

Thanks for the reply I've just been looking through the folder of receipts and it's mainly had Mobil 1 from what I can find . I'm near Grantham mate .

langer

iTrader: (1)

I use 10/60 every time. 5 is way to thin for a cossy. Every time this question pops up it opens a whole can of worms so to speak.

MARCOSWORTH

iTrader: (24)

Fuchs Titan Pro-S 10W50 as 10W60 is thicker than necesarry and will not flow or protect as well as the 10W50 from Fuchs

Cossie Sean

Silkolene Pro-R 10-60 for me, and its red so easy to see where the YB`s are pumping it out of lol

we used to run pretty much every gpA/N car on this too

ajamesc

id have said 10w50 but i use fully syn 10w40 in mine as its on tap at work so free!

MrC

i was using mobil 1 15/50 which worked well, now using fuchs 10/50

essex-monkey

Thought there would be a lot of different responses, think I'll use Mobil 1 15/50 as I think that's what is been using , I guess any thinner and the engine will start depositing it over my drive lol , thanks Everyone for the input.

Matt Lewis

iTrader: (2)

15-50 has been replaced now with 10-60, however my customers believe that 10-60 is far better than the 15-50

essex-monkey

Hi Matt , thanks for that info I'll get my work to order me some .
I've just ordered my oil sensor with you on eBay ( I assume it's u )

Matt Lewis

iTrader: (2)

thanks mate.............sensor posted this evening

andycos

I used mobil 1 15/50 in my Cosworth for the last 12 years,but i have now gone over to Shell 15/50 (again fully synthetic) and it works great on it to

martysmartie

iTrader: (1)

Fuchs 10W/50 for me. I woulden't use anything less than a fully syn 50 weight.

Nothing wrong with Mobil either as it's liked by others.

Don't use 5W/30, it's too thin for these or any old engines, it's not so much that it will leak but it won't protect the engine properly, and it may burn it, remember these engines don't have the close tolerances of modern engines!

Martin

essex-monkey

Just fed it some Mobil 1 15/50 and seems to like it

Roll on weekend driving !

Thanasis

iTrader: (3)

Liqui Moly 10w/60 great oil,and quickly as cold!

mattman1234

when people say an oil works well,,how can you tell between them.say you put in a 5 grade oil ,tried it,then drained,then tried a 15 grade oil.Now i ask ,what were the differences ?

martysmartie

iTrader: (1)

It's just known that it works well, 5W is just sense really that it's to thin for this sort of application, and my theory is that a 50 weight will give good protection when hot, i.e. it won't break down and fully synthetic for top quality.

I guess some people who have tried the wrong vicosity etc may had a bad experience, hence why when they use something decent and it runs well thats there idea of "working well" lol.

Martin

chrisa3

iTrader: (1)

Ive just changed from Castrol GTX to the new Mobil 1 1ow60 and its Shit imo. It was like pouring syrup into the engine. I knew pouring it in what was going to happen, i was thinking 'that cant flow very fast when its cold,' and sure enough, rattled its tits off. not very happy. The oil pressure readings are a little bit better than with the GTX but only 2-3 psi higher at cold or hot. That was a waste of Ł40 quid. Might try some Millers 10w50 before going back to the good old Castrol GTX.

Sonic Boom

iTrader: (11)

Motul 300V Competition 15W-50
Rich

Cossiemainful

iTrader: (1)

Not all 10W-60 are good. For cold days it's way too thick, even if its 10W.... to much torture for the bearings etc. and you need a longer warm-up time.

So many urban legends about the oil. 5W isn't too thin, it is only the cold visco. A 15W-50 is too thick for cold days and bit thinner at temperature. A 5W-50 is very well and strong for cold and hot driving.

Even a Mobil 1 0W-40 is stronger than most people think (forget the myth about the engine is too old, way older engines tolerate 0W-40). First filling by Porsche, BMW and so on. Only the hot visco after the W can be too thin (for example a 0W-20 or 30 were too thin) but never a cold visco. People have to mind this fact.

the biggest difference about the cold and hot visco is the best (exceptions some ester oils):
0W-40 (not 5W- 10W- 15W-40)
5W-50 (not 10W- 20W-50)
10W-60 (not 20W-60)

Sometimes less is more.

Had never much oil consumption in the cossie with 0W-40. But now I've 5W-50 for the daily driver.

Rsmat

iTrader: (2)

Think I'm going to give the castrol GTX a go..., is it the 10/40 everyone uses..?

chrisa3

iTrader: (1)

I used the 15w40, it was Ł10 in Asda on special offer. Engine was smooth and quiet. I would say that after 30 minutes of hard driving, the oil pressure was slighlty lower lower (2-3 psi, so not much) than usual operating temps, which showed it was thinning out a bit under heat. This is why I went with some recommendations and got the Mobil 1. Wished i never bothered. Going to try some Pro s 10w50 and if that doesnt improve things, I'll be switch back to the GTX.

Rsmat

iTrader: (2)

I've tried pro S it was good.

ajamesc

The difference between a 5w and a 15w is how thin they are when cold so a 15 will be thiner than a 5 which will be to thin! 10 is about right! the other number be it 40/50 or 60 is how thick the oil is when warm 40 could be said to be to thin and could cause weeping oil leaks i use a 40 in mine a 10w40 as its free thats what we have on tap at work i have good oil pressure cold and hot and no real oil leaks! You could also say a 60 is a bit to thick most tend to use a 10w50! You have to remember all the small oil ways and fine tolerances in an engine so oil thats to thick will not ciculate as it should plus oil thats to thin will give a lower oil pressure and not protect the engine as well as it should causeing things to wear faster

Rsmat

iTrader: (2)

Will I be ok to try the 10/40 then..?

ajamesc

I have no probs with it in mine and have good oil pressure but only use it as its what we have at work its fully syn 10w40 from shell i use but if i had to buy my oil i would use 10w50

v man

shell helix from the petrol stations is ment to be good cossie oil

cheap to

Toe Knee

iTrader: (2)

For the castrol people it was mentioned a while back by opies oil it wasn't too great once at running temps as other oils were hence more people use other brands. I used mobi 1 15/50 till they changed it to 10/60. Did an oil change the other day and have to agree with chrisa it did seem to rattle a bit to start but did clear up and hasn't seemed to since. Plus the fact it's available from every halfords is why I prefer using it!!

MrC

Cravendale milk, it's magical stuff

chrisa3

iTrader: (1)

Well, I switch to Silkolene Pro S 10w50 and it seems to have quietened things down. I still have a residual tappet 'rattle' at idle even when hot, though the oil pressures etc are all good. Im guessing that the lifters on mine were on their way out and switching to the Mobil 1 has caused 1 or 2 to fail. going to stick some new lifters in while the oils new. more money

martysmartie

iTrader: (1)

The hydraulic tappets can make a noise sometimes, usually it's when one or more gets blocked, this is why, as with any car with them it's important the oil is changed as the lifters get clogged otherwise, and that the correct oil is used, not saying this in your case.

Mine only tends to rattle when I start from cold and they can take a few minutes to settle down, but once it's warmed up the engine is very quiet!

Look for 'INA' if buying new, you can if you are really determined dismantle the old lifters and clean them, also Wynns do a "hydraulic lifter lube", that may be worth a try before hand.

Martin

gibbo frst

iTrader: (2)

i use silkolene 10/60 in mine . used the older 10/50 silkolene and didnt notice any difference.. maybe a tiny bit more oil pressure.. no tappet noise hot or cold..
used to use mobile1 im my old engine and never had a problem with that either..

Cosnada

iTrader: (2)

This bloody thread lol.............

I used to wait when Halfords had a sale on and get 3 for 2 etc. I used to buy the silver 5w40 fully sinthetic and had no issues even track days.

Now, I read this thread and think ooops, may be its a little too thin (not too worried about the cold side as only a summer / track car) and with the extra miles that add up then a decent oil might be a good idea.

Went into Halfords and went passed all the usual stuff but all I could find was 0w30, 5w30 etc. Not happy with that I decided to go to my local motorists shop. They had one can of Mobil 1 15w50 - I took it Ł50 bastard quid tho
I too was tempted to use Castrol GTX at Ł17 when I was in Halfords but decided against it due to it only being semi synthetic and the hard labour mine gets on track days.

Maybe piece of mind does cost a little more and when running a YB we should not scrimp on such vital things as oil. With everything else being so expensive though it would be nice to find the holy grail in oil if its out there.

HidetoshiNemoto

I take what Rouse says

carl/saff

I use 10/60 in my Saph.....rebuilt 1 year ago.

chrisa3

iTrader: (1)

Those were the days of Duckhams Hypergrade etc. The Shell Gemini was 15w50 Semi-Synthetic, along with all the other oils that were recommended back in the 80's.

chrisa3

iTrader: (1)

Even the bloke with the posh voice thinks its the best

http://www.youtube.com/watch?v=m5PLJVgWTZw

Think its a 3dr in this one as well

http://www.youtube.com/watch?v=NI3PlFwSFQ0

Toe Knee

iTrader: (2)

Cosnada halfords do the 10/60 now instead of the 15/50!!

HidetoshiNemoto

oh my point is 15w50 spec. 50 is what must meet says in the owners manual

I will be using this for the rest of her life!!!!